alpha-Synuclein (alpha-syn), an aggregation-prone amyloid protein, has been suggested as a potential cause of Parkinson's disease. When misfolded, alpha-syn aggregates as Lewy bodies in the brain, the loss of which can disrupt protein homeostasis. To investigate the potential of nanoparticle-mediated therapy for amyloid diseases, alpha-syn adsorption onto positively charged poly(allylamine hydrochloride) coated gold nanoparticles (PAR Au NPs) was studied. alpha-Syn adsorbs in multilayers onto PAH Au NPs, which with increasing alpha-syn/PAH Au NP ratios (>2000 alpha-syn/PAH Au NP) results in the flocculation and sedimentation of alpha-syn coated PAH Au NPs. The orientation and conformation of alpha-syn on PAR Au NPs were studied using trypsin digestion and circular dichroism, which showed that alpha-syn adopts a random orientation on PAR Au NPs, with an increase in beta-sheet and a decrease in alpha-helix structures. A consistent global change in alpha-syn's conformation was also observed regardless of PAR Au NP concentration, suggesting bound alpha-syn initiates conformational changes to free alpha-syn.